1947, and an M.A. in physics in 1950, all three from Cambridge University. He then began working as a radar engineer.

In 1959, while doing research on radar at Westinghouse, he obtained a Ph.D. from Johns Hopkins University, thereby beginning his long-standing relationship with Johns Hopkins. He received an honorary degree of doctor ofhuman letters from the university in 1989 and was presented the Woodrow Wilson Award for Distinguished Government Service in 2001. He also served on several advisory committees of the Whiting School of Engineering, including the Dean’s Advisory Committee, for many years.

From 1960 to 1973, Leo led a group of researchers at the Stanford Research Institute in California, while teaching courses at Stanford University and at the Technion, the Israel Institute of Technology. In 1974, he joined the Naval Research Laboratories in Washington, D.C., then moved to the Office of the Secretary of Defense (OSO) as director of research, which included oversight of the Army/Navy/Air Force/DARPA basic research programs. In addition, he led the University Research Initiative, which promoted multidisciplinary research. Leo was also a supporter of the establishment of the Small Business Innovation Research (SBIR) Program.

In 1969, Leo became president of the Microwave Theory and Techniques Society (IEEE MTT-S). He was presented an MTT-S Prestigious Microwave Prize in 1963 and a Microwave Career Award in 1988. In 1982, he became an honorary life member, and in January of 1980 he became president of IEEE.

Leo retired from his government position in 1994, but he continued working as a consultant and a member of the board of Filtronic. In 1997, Leo became a foreign member of the Royal Academy of Engineering (U.K), and in 1999, he was elected a member of the National Academy of Engineering (NAE). In 2005, NAE presented him with the Arthur M. Bueche Award “for leadership in sponsoring collaborative research programs among academic, industrial, and government engineers and scientists.”